British scientist Brian Cox says we are unlikely to find aliens because intelligent life destroys itself not long after it evolves.
On a clear night up to around 2500 stars can be seen in the sky. But this is roughly one hundred-millionth of the stars in our galaxy. Almost all of them are less than 1000 light years away from us - that's far, but is still only 1 per cent of the diameter of the Milky Way.
So with so much potential for other life forms around us, why haven't we found any?
According to the Sunday Times Brian Cox thinks he has the answer. He said it's because the advances in technology and science needed to reach other life forms, would destroy the political institutions needed to organise the search.
Cox suggests technology that creates carbon dioxide (CO2) emissions and nuclear weapons could destroy civilisations - including our own - before there was a chance of finding other life.
Cox is trying to answer the Fermi paradox. In 1950 physicist Enrico Fermi questioned why we hadn't encountered alien life given modest rocket technology plus ten million years could equal a take over of the Milky Way pretty easily.
Cox agreed and said, "One solution to the Fermi paradox is that it is not possible to run a world that has the power to destroy itself and that needs global collaborative solutions to prevent that".
"It may be that the growth of science and engineering inevitably outstrips the development of political expertise, leading to disaster," Cox said, according to The Daily Mail